People have been building these lovely boxes for a very long time, so I doubt I could ever dream up anything that hasn't been done before, but I recently devised and built a jig that I'm kind of excited about.
The problem I was trying to overcome was that of keeping the blocks properly aligned while closing the box. Using standard external molds and internal spreaders has worked well enough for me in the past, but I kept wondering if I might be able to control the geometry of the neck block more accurately from outside the box, as opposed to inside. That's hard to do when you have an external mold and its fasteners in the way.
This is kind of hard to describe and a picture is worth a thousand words, so here's a shot of what I've built:
Basically, I place the rims and plate in the appropriate solara (or radiused dish) and fit them between two right angle cauls. (One thing you don't see in this photo is that the top plate should be secured in place by a caul tightened through the soundhole.) The adjustable cauls are then forced together and locked in place once the blocks are determined to be level and square. This does require me to move things during the process, which flies in the face of the idea that everything stays in the mold until the box is completely closed. However, this allows me to double-check things after the first plate is on and before the second plate has been affixed, which I found difficult to do using an external mold and spreaders.
This also requires me to drill small holes through both blocks. Not a big deal to me as I'm going to do that anyway, but this may not work for everyone.
As I said above, everything has been done before and it may be that the reason I've never seen anything exactly like this is because it's a really dumb idea. I'd love to know what you all think about this, if only to save myself a lot of heartache later!
